The Washington University SCOR in Thrombosis is focused on investigation of basic, pathogenic mechanisms involved in thrombotic disease in man. Utilizing techniques of the interactions of clotting factors with one another and with model lipid surfaces, as well as with platelets. Additionally, the relationship between coagulation factors, platelets, and the cellular elements of the blood vessels is under investigation. Another area of investigation is in the use of isotopic techniques for analysis of in vivo coagulation dynamics and for improved procedures for the diagnosis of thrombosis in experimental animals and man.